Wiper for plunger pumps



Nov. 13, 1962 H. H. LOWERY WIPER FOR PLUNGER PUMPS Filed Jan. 3, 1961 .17 g? 25- i z #5800 A4 LOWEQY INVENTOR.

BY g x Unite States Patent i 3,063,764 WIPER FOR PLUNGER PUMPS Herod H. Lowery, 124 Woodlawn St., Taft, Calif. Filed Jan. 3, 1961, Ser. No. 80,250 3 Claims. (Cl. 30954) This invention relates to apparatus for use in pumpin oil from oil wells and in particular relates to a device to be used in conjunction with a plunger type pump.

In pumping the fluid from an oil well one of the conventional methods employs the use of a plunger with a central bore. The exterior of the plunger closely fits the interior of a liner or tubing so that when the plunger is lowered any fluid below the plunger is forced up through the bore in the plunger. By the use of appropriate check valves the fluid is progressively raised to the surface by continued reciprocation of the plunger.

When the exterior of the plunger or the interior of the liner or tubing adjacent the plunger becomes worn, the fluid bypasses the exterior of the plunger rendering the pump ineffective. In numerous oil wells there are sand particles suspended in the fluid being pumped which acts as an abrasive to increase the objectionable wearing of the plunger. Further, the presence of sand between the plunger and the liner or tubing encourages the plunger to stick on the downstroke rather than dropping freely to begin the next upstroke.

The rapidity of wear and the cost of each replacement in some wells can create an uneconomical and objectionable maintenance condition resulting in a relatively unprofitable oil well.

Although some plungers are available with cups which reduce the effects of the sand on the plunger, these plungers are incapable of operation in relatively deep wells. Also, if the stroke of the plunger carries any of the cups out of the liner or tubing those cups will be damaged and rendered ineffective.

Accordingly, a principal object of this invention is to provide a plunger of the type described with means for preventing sand from coming in contact with the exterior of the plunger.

Another object of this invention is to provide a device which can be installed on any oil well pump plunger to protect the plunger from sand present in the fluid.

Another object of the present invention is to provide a device to reduce the wearing of a plunger caused by sand and which has means for excluding the sand capable of conforming to the exact shape of liner or tubing.

Another object of this invention is to provide a device having means which compensate for wear and exclude sand from the plunger.

Another object of this invention is to provide a device which may be reciprocated beyond the liner or tubing without rendering it ineffective.

Other and more detailed objects and advantages of this invention will appear from the following description and the accompanying drawings.

In the drawings:

FIGURE 1 is an elevational view of the device, without the packing elements, constituting the preferred embodiment of this invention.

FIGURE 2 is an elevational view of two of the devices installed on either end of a conventional plunger and shown in a liner.

FIGURE 3 is an enlarged detail of a sectional view taken substantially on lines 3-3 of FIGURE 2.

FIGURE 4 is a sectional view taken substantially on lines 4-4 of FIGURE 3.

Referring now to the drawings, the wiper, generally designated 10, has a central bore 11 extending through body 12. One end of the body is provided with an externally threaded portion 13 and the other end 14 is provided with an internally threaded portion (not shown). A series of grooves 15 are provided in the exterior surface of the body 12.

A length of packing material is positioned in each groove 15 to form a packing ring 16. The packing material is preferably square or rectangular in cross-section as best shown in FIGURE 3. While any suitable packing material may be used, I prefer to use a composition which expands when brought in contact with the crude oil present in the well in which the wiper is to be installed.

The width of each groove 15 between radially extending surfaces 17 is smaller than the width of the packing material, thereby requiring the packing material to be forced into the groove 15 and discouraging subsequent disassembly. The radial depth of the groove 15 is adapted to accommodate and support the packing material for engagement with the cylinder in which it is inserted.

A wiper 10 is installed on each end of the pump plunger 18 which plunger may be of any ordinary design.

The plunger has a central bore 19 communicating with V the central bore 11 in the wiper body 12 to provide a passage for the flow of the fluid being pumped. The plunger-wiper assembly is reciprocated in the tube 20 which may be oil well tubing or a liner. The diameter of the outer surface 21 of plunger 18 is just slightly less than the diameter of the inner surface or pump barrel 22 of the tube so that no appreciable amount of fluid may flow past the outside of the plunger.

The diameter of the outer surface 23 of the wiper body 12 is less than the diameter of the outer surface 21 0f plunger 18 thereby permitting fluid flow between the exterior of the wiper body and the interior of the tube 20. However, this fiow between the tube and the wiper is inhibited by the packing rings 16 which are of suflicient outside diameter to circumferentially engage the bore f the tube 20.

In operation the packing rings 16 serve to wipe the bore of the tube 20 as the plunger-wiper assembly is reciprocated thereby preventing any solid impurities such as sand from coming in contact with the exterior of the plunger. The series of rings 16 is provided to present a multiple barrier to exclude solid impurities and allow for wear without requiring placement. Also, as each ring 16 wears, if the preferred material is used, it will expand to compensate for that wear.

A relatively small space is required between the grooves 15, thus permitting a great number of rings 16 in a short wiper 10, thereby providing optimum durability with a minimum increase in the length of the pumping apparatus.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details herein set forth or to the details illustrated in the drawings, but my invention is of the full scope of the appended claims.

I claim:

1. In a wiper adapted to be connected to either end of a well pump plunger, the combination of: a tubular body having threaded connecting means on each end, a plurality of axially spaced and circumferentially extending grooves in the exterior surface of said body, a ring of compressible-expansible packing in each said groove, and the diameter of the exterior of said body being everywhere substantially less than that of the plunger whereby the fluid pumping is accomplished by the said plunger.

2. In a wiper adapted to be connected to either end of a well pump plunger, the combination of: a tubular body having threaded connecting means on each end, a plucompressible-expansible packing .in each said groove, each References Cited in the tiletof this patent said ring having a normal outside diameter equal to or greater than the outside diameter of the plunger, and the UNITED STATES PATENTS diameter of the exterior ;of said body being everywhere 20574 Martin V D66' 7, 1937 substantially less than that .of the plunger whereby the 5 1 549 940 (Wells gt a1 Aug 18 1925 fluid p p q p e y th aid plu g 1588705 a et June 1926 3- The combination of claim 2 In which the material 1,923,040 pp g 1933 of the said rings expands substantially when brought in contact with the fluid pumped whereby th id rings 2,097,629 LOWETY 1937 compensate for wear thereof. 10 2,344,687 Fischer et a1. Mar. 21, 1944 

